Focus on levelling your sentry. Once you've got that near max then every node is effectively a turret. Combine that with a well thought out layout and you'll have more luck. No base is unhackable though.

This game is marvellous. I'm disabled and mostly housebound so keeping my mind active is crucial. This game has proved to be an elegant and challenging experience. One of those rare occasions where I wish I could unlearn everything and start afresh repeatedly. I agree with others that a "guild" like...